The story sounds familiar – while the use of unmanned, sometimes illegally, is increasing, there are myriad challenges to ultimately allow them safe access to national airspace.

The watchdogs at the Government Accountability Office issued report on the integration of unmanned aerial systems as it calls them, in US national airspace (NAS) today ahead of a congressional hearing on the topic. As it has noted in past reports, the GAO said the main issues continue to include the ability for drones to avoid other aircraft in the sky; what backup network is available and how should the system behave if it loses its communications link.

“As we previously reported, research and development continue in areas related to a UAS’s ability to detect and avoid other aircraft, as well as in command and control technologies and related performance and safety standards that would support greater UAS use in the national airspace. The DOD and NASA are conducting some of this research. Until this research matures most UAS operations will remain within visual line of sight of the UAS operator,” the GAO report states.

Not everyone is waiting for the FAA though. The GAO noted “some individuals are conducting domestic operations illegally or unsafely. For example, one UAS nearly collided with a New York Police Department helicopter over New York City, another came dangerously close to a Us Airways regional jet over the Florida panhandle, and numerous UASs have been spotted flying over professional and college football stadiums full of people.”

Outside of the US drones are indeed making headway way into general airspace. The GAO says Japan, Australia, United Kingdom, and Canada also allow more commercial UAS operations than the United States. According to a study by Mitre, the types of commercial operations allowed vary by country. For example, as of December 2014, Australia had issued over 180 UAS operating certificates to businesses engaged in aerial surveying, photography, and other lines of business.

Furthermore, the agriculture industry in Japan has used UAS to apply fertilizer and pesticide for over 10 years. Several European countries have granted operating licenses to more than 1,000 operators to use UASs for safety inspections of infrastructure, such as rail tracks, or to support the agriculture industry, the GAO says.

What is garnering a lot of public attention in the US is the forthcoming FAA rules about how small drones can operate in US airspace.

The GAO says that the FAA must first issue a Notice of Proposed Rulemaking (NPRM). The small UAS rule (generally, UAS size is considered small or large based on weight. Under the 2012 Act, small UASs are defined as weighing less than 55 pounds, thereby leaving those UASs 55 pounds or more being described as large) is expected to establish operating and performance standards for a UAS weighing less than 55 pounds, operating under 400 feet, and within line of sight. FAA officials told us in November 2014 that FAA is hoping to issue the NPRM by the end of 2014 or early 2015.

The GAO notes that there are some in the industry who say the FAA’s small UAS rule may not resolve issues that are important for some commercial operations. One stakeholder told the GAO they expect the proposed rule to authorize operations of small UASs only within visual line of sight of the remote operator and to require the remote operator to have continuous command and control throughout the flight. According to this stakeholder, requiring UAS operators to fly only within their view would prohibit many commercial operations.

According to FAA, its goal is to issue the final rule 16 months after the NPRM. If this goal were met, the final rule would be issued in late 2016 or early 2017, about two years beyond the requirement of the congressional mandate.

“The FAA told us that it is expecting to receive tens of thousands of comments on the NPRM. The time needed to respond to such a large number of comments could further extend the time to issue a final rule. FAA officials told us that it has taken a number of steps to develop a framework to efficiently process the comments it expects to receive,” the GAO stated.

Some other interesting facts from the GAO report:

The GAO has previously reported that NASA and DOD have extensive research and development efforts supporting integration into the NAS. Other areas of focus and progress by FAA include command and control, as well as operations and approval. According to FAA, progress for command and control was marked by identifying challenges for UAS operations using ground-to-ground communications. The FAA also indicated it conducted simulations of the effects of UAS operations on air traffic management.

In support of research and development efforts in the future, FAA solicited for bids for the development of a Center of Excellence. The Center of Excellence is expected to support academic UAS research and development for many areas including detect and avoid, and command and control technologies.

NASA has a $150-million project focused on UAS integration into the conduct research that reduces technical barriers associated with UAS integration into the NAS, including conducting simulations and flight testing to test communications requirements and aircraft separation, among other issues. The DOD has research and development efforts primarily focused on airspace operations related to detect and avoid systems. However, DOD also contributes to research and development focused on certification, training, and operation of UAS.

Several federal agencies and private sector interests have research and development efforts under way to develop technologies that are designed to allow safe and routine UAS operations. The GAO says agency officials and industry experts told them that these research and development efforts cannot be completed andvalidated without safety, reliability, and performance standards, which have not yet been developed because of data limitations.

Other areas of focus and progress by FAA include command and control, as well as operations and approval. According to the FAA, progress for command and control was marked by identifying challenges for UAS operations using ground-to-ground communications. The FAA also indicated, during our ongoing work, that it conducted simulations of the effects of UAS operations on air traffic management.